Polycarbonate (PC) compound materials are prepared by melt-mixing PC, which is widely used as an engineering plastic, with organic/inorganic materials, such as heat stabilizers, antioxidants, plasticizers, impact modifiers, flame retardants, inorganic fillers, and the like. Such PC compound materials exhibit superior properties to general resins such as polystyrene, polyethylene, polyvinyl chloride, polypropylene, and the like. In particular, since the PC compound materials allow easy adjustment of properties, such as impact resistance, flame retardancy, flowability and the like, the PC compound materials are applicable to various fields from electric/electronic products such as mobile phones, televisions, office machines and the like to industrial components and miscellaneous goods.
Recently, as plastic products have become lighter and thinner to achieve more eco-friendly designs, demand for novel PC compound materials simultaneously exhibiting various properties which are difficult to realize in existing PC compounds has increased.
Generally, PC compound materials can obtain suitable properties by adjusting a mixing ratio of organic/inorganic materials to be melt-mixed with PC. For example, Korean Patent Publication No. 10-2008-0063229A, No. 10-2010-0125344A, and the like disclose thermoplastic resin compositions prepared by melt-mixing PC with a cross-linkable rubber-modified impact modifier, a phosphorus flame retardant, and other additives. However, such thermoplastic resin compositions require an excessively large amount of the phosphorus flame retardant for realization of high flowability, thereby causing deterioration in heat resistance.
Korean Patent Publication No. 10-2007-0052820A discloses a resin composition having improved flowability through application of a PC oligomer. However, since such a PC oligomer has a relatively low weight average molecular weight ranging from 3,000 g/mol to 6,000 g/mol, the composition can suffer significant deterioration in impact resistance and elongation, despite improved flowability.
Thus, there is a need for a flame retardant thermoplastic resin composition that exhibits excellent properties in terms of impact resistance, oil resistance, flame retardancy and flowability, even when melt-mixed with flame retardants, impact modifiers, and the like.